all agriculture stories

Invention of cooking drove evolution of the human species, new book argues

50443248 — Mon, 01 Jun 2009 14:33:34 -0400

“You are what you eat.” Can these pithy words explain the evolution of the human species?

Yes, says Richard Wrangham of Harvard University, who argues in a new book that the invention of cooking — even more than agriculture, the eating of meat, or the advent of tools — is what led to the rise of humanity.

Culture skews human evolution

50443248 — Thu, 12 Mar 2009 15:32:21 -0400

The rise of agriculture 10,000 years ago meant the end of the hunter-gatherer lifestyle for which human beings had been optimized by millions of years of evolution and the beginning of an era where culture encourages habits unhealthy for us and for the world around, with uncertain evolutionary outcomes.

“Our bodies are not that well designed for the world we have created,” said anthropology professor Daniel Lieberman.

Tamed 11,400 years ago, figs likely first domesticated crop

70652986 — Mon, 26 Mar 2007 06:27:59 -0400

Archaeobotanists have found evidence that the dawn of agriculture may have come with the domestication of fig trees in the Near East some 11,400 years ago, roughly 1,000 years before such staples as wheat, barley, and legumes were domesticated in the region. The discovery dates domesticated figs to a period some 5,000 years earlier than previously thought, making the fruit trees the oldest known domesticated crop.

Ofer Bar-Yosef of Harvard University and Mordechai E. Kislev and Anat Hartmann of Bar-Ilan University reported their findings in the journal Science.

"Eleven thousand years ago, there was a critical switch in the human mind - from exploiting the Earth as it is to actively changing the environment to suit our needs," says Bar-Yosef, professor of anthropology in Harvard's Faculty of Arts and Sciences and curator of Paleolithic archaeology at Harvard's Peabody Museum of Archaeology and Ethnology. "People decided to intervene in nature and supply their own food rather than relying on what was provided by the gods. This shift to a sedentary lifestyle grounded in the growing of wild crops such as barley and wheat marked a dramatic change from 2.5 million years of humans as mobile hunter-gatherers."

The research was sponsored by the American School of Prehistoric Research at Harvard's Peabody Museum, the Israel Museum in Jerusalem, the Shelby-White-Leon Levy Foundation, and the Koschitzky Foundation at Bar-Ilan University.

Eating plants that grow on plants

70652986 — Mon, 26 Mar 2007 06:26:23 -0400

Parasitic plants are not just a biological curiosity. Every year, parasitic plants damage farmers' fields, particularly in Africa. Kristin Lewis, a junior fellow at the Rowland Institute at Harvard, is learning more about plants and their parasites.

For instance, in Africa, seeds of parasitic plants blow in from surrounding environments or are deposited in bird droppings. The plants that grow from those seeds attach to roots and stems, sucking vital nutrients, stunting the crop plants' growth, and reducing yields.

To foil the parasites, African farmers have adopted the practice of planting fields twice, first with plants that are resistant to the parasites and then, after the parasites germinate and die, with their desired crop, such as sorghum.

"Most of them are very problematic plants," Lewis said.

Lewis became interested in parasitic plants while studying plant defenses. Though they can't fight back as an animal would, plants can generate a wide variety of substances that are toxic or distasteful to insects and other browsers.

In fact, some of our best-known commercial plants are popular exactly because of the unique qualities of the plant's chemical defenses. Caffeine and nicotine, for example, as well as the hot spices contained in pepper plants, are all intended by the plant to discourage herbivores.

After studying plants' reactions to insects eating their leaves, Lewis became interested in the interaction of a plant and its parasite.

She already knew that in some cases a parasitic plant shares the host plant's defensive chemicals, as well as nutrients and carbohydrates. What she wants to find out is how much the two plants communicate.

If an insect attacks a parasitic plant, that insect is just a short distance from the host plant. Though normally the host wouldn't benefit from helping its parasite, it's possible the parasite could manipulate the host into shifting more defensive chemicals into the parasite to keep the leaf-eating insect at bay - over there. That would require some sort of communication from the parasite to the host saying, in essence: "Send help fast. It's BITING me!"

Lewis said she's still gathering data, but she remains fascinated by the active responses to the environment of plants, which on the surface seem so passive.

Beetle mania

70652986 — Mon, 26 Mar 2007 05:25:38 -0400

Grain weevils alone cost the global economy about $35 billion, or a third of the world's grain crop, every year. Various other beetle species damage dozens of crops including bamboo, palm trees, bananas, grasses, sugarcane, pines, and irises. "My research is about the evolution of interactions of various sorts," Professor Brian D. Farrell says, "including those with plants, those with fungi that help insects attack plants, and those with bacteria that help insects digest plants." His main focus of late has been on bark beetles, which cause about $7 billion of timber damage in the United States alone. "We spend tens of millions of dollars every year studying all aspects of their biology," he says.

Mustard shows backbone in its own defense

70652986 — Mon, 26 Mar 2007 05:20:26 -0400

Over the past few years, accumulated evidence from many scientists suggests that plants, animals, and insects share common elements in their innate skirmishes with potential pathogens. In the Feb. 28, 2002 issue of the journal Nature, plant scientists at Massachusetts General Hospital and Harvard and their colleagues have reported another striking similarity. The researchers identified the step-by-step process from the sentry guarding the cell perimeter to the deployment of the defensive immune mechanisms. The details from danger signal to action were worked out in isolated cells of the mustard Arabidopsis thaliana.

'Evergreen Revolution' called for

70652986 — Mon, 26 Mar 2007 05:10:56 -0400

M.S. Swaminathan, a world-renowned agricultural scientist, outlined a plan that focuses on educating women in developing countries, getting new technology out to rural areas, and incorporating into farming practices scientific advances such as genetically engineered crops and new techniques to conserve water. "If the future is to be truly sustainable, it must have all these factors: economics, equity, and employment," said Swaminathan, who addressed about 100 people who gathered March 9, 2001, in the Science Center at Harvard University. Swaminathan's lecture was sponsored by the University Committee on the Environment, the School of Public Health's Program on Water and Health, the Working Group on Environmental Justice and the Education Development Center Inc.